Many products, such as wall panels, wall coverings, and decorative tiles, are made of a wide variety of materials. These materials include corrugated paper, textiles, glass, glass fiber, metals (such as tin, steel, and aluminum), ceramics (such as porcelain), wood, and plastics. For many of these products some of these materials have good mechanical properties and surface quality; some are inexpensive and affordable; and some are highly resistant to mold and/or mildew.
Unfortunately, though, for many products none of these materials individually have good mechanical properties, good surface qualities, is inexpensive, and highly resistant to mold and mildew. In addition, many of these materials have other drawbacks. For example, many include chemical additives such as, volatile organic compounds (VOCs), that can be harmful to people and/or the environment. Many do not provide good thermal insulation, which can cause excessive energy consumption. Many are not easily recyclable. And, many are not lightweight, and thus, require more energy to transport and stronger structures to support and hold the products during use.
A possible alternative to such materials are thermoplastic polymers because they are inexpensive, highly resistant to mold and/or mildew, and can be easily formed into shapes that can provide good mechanical properties when subjected to a particular loading, and can be made to have a good surface quality. Thermoplastic polymers can also be made very light by foaming them to generate a material structure that includes many cells, and they can be easily recycled.
Thermoplastic polymers are frequently manufactured in thin sheets that are then wound around a spool. When manufactured in this manner, the thin sheet is typically used to make components that are also thin. When such a sheet is used to make a component that is thicker than the sheet, the sheet is cut into sections and then each section is joined to the other sections to form a laminate. Adhesion bonding and/or fusion bonding typically join the sections together. Adhesion bonding includes applying an adhesive to a surface of a section and then pressing the two sections together while the adhesive cures. Fusion bonding includes melting a surface of both sections, and then pressing the sections together while the two molten surfaces coalesce. Then the coalesced surfaces are cooled to solidify them as one material.
Unfortunately, adhesion bonding typically releases VOCs as the adhesive cures, and fusion bonding requires very delicate control of the process to maintain the general shape of the laminate as the surfaces are melted, coalesce, and solidify.